<?php

// Disable error display in the output
require_once dirname(__DIR__) . '/helpers/ErrorHandler.php';
ErrorHandler::init();

// Apply rate limiting
require_once dirname(__DIR__) . '/middleware/RateLimitMiddleware.php';
RateLimitMiddleware::apply('api');

// Start output buffering to capture any errors
ob_start();

try {
    // Include required files with proper error handling
    $configPath = dirname(__DIR__) . '/config/config.php';
    $commentModelPath = dirname(__DIR__) . '/models/CommentModel.php';
    $auditLogModelPath = dirname(__DIR__) . '/models/AuditLogModel.php';

    if (!file_exists($configPath)) {
        throw new Exception("Config file not found: $configPath");
    }

    if (!file_exists($commentModelPath)) {
        throw new Exception("CommentModel file not found: $commentModelPath");
    }

    require_once $configPath;
    require_once $commentModelPath;
    require_once $auditLogModelPath;
    require_once dirname(__DIR__) . '/helpers/Database.php';
    require_once dirname(__DIR__) . '/models/TicketModel.php';
    require_once dirname(__DIR__) . '/helpers/NotificationHelper.php';
    require_once dirname(__DIR__) . '/helpers/SynapseHelper.php';

    // Check authentication via session
    if (session_status() === PHP_SESSION_NONE) {
        session_start();
    }
    if (!isset($_SESSION['user']) || !isset($_SESSION['user']['user_id'])) {
        ob_end_clean();
        http_response_code(401);
        header('Content-Type: application/json');
        echo json_encode(['success' => false, 'error' => 'Authentication required']);
        exit;
    }

    // CSRF Protection for all state-changing methods (any non-GET/HEAD request)
    require_once dirname(__DIR__) . '/middleware/CsrfMiddleware.php';
    if (!in_array($_SERVER['REQUEST_METHOD'], ['GET', 'HEAD'], true)) {
        $csrfToken = $_SERVER['HTTP_X_CSRF_TOKEN'] ?? '';
        if (!CsrfMiddleware::validateToken($csrfToken)) {
            http_response_code(403);
            header('Content-Type: application/json');
            echo json_encode([
                'success' => false,
                'error' => 'Invalid CSRF token',
                'csrf_token' => CsrfMiddleware::getToken()
            ]);
            exit;
        }
        // Rotate token after successful validation
        $newCsrfToken = CsrfMiddleware::rotateToken();
    }

    $currentUser = $_SESSION['user'];
    $userId = $currentUser['user_id'];

    // Use centralized database connection
    $conn = Database::getConnection();

    // Get POST data
    $data = json_decode(file_get_contents('php://input'), true);

    if (!$data) {
        http_response_code(400);
        ob_end_clean();
        header('Content-Type: application/json');
        echo json_encode(['success' => false, 'error' => 'Invalid JSON data received']);
        exit;
    }

    // Validation, access check, mentions, audit log and notifications live in
    // CommentService so the MCP add_comment tool runs the same code path.
    require_once dirname(__DIR__) . '/services/CommentService.php';
    $result = CommentService::addComment($conn, $currentUser, $data);

    if (!empty($result['http_status'])) {
        http_response_code($result['http_status']);
        unset($result['http_status']);
        ob_end_clean();
        header('Content-Type: application/json');
        echo json_encode($result);
        exit;
    }

    if ($result['success'] && isset($newCsrfToken)) {
        $result['csrf_token'] = $newCsrfToken;
    }

    // Discard any unexpected output
    ob_end_clean();

    // Return JSON response
    if ($result['success']) {
        http_response_code(201);
    }
    header('Content-Type: application/json');
    echo json_encode($result);
} catch (Exception $e) {
    // Discard any unexpected output
    ob_end_clean();

    // Log error details but don't expose to client
    error_log("Add comment API error: " . $e->getMessage());

    // Return error response
    http_response_code(500);
    header('Content-Type: application/json');
    echo json_encode([
        'success' => false,
        'error' => 'An internal error occurred'
    ]);
}